Copper Lake
Copper Lake in Cook County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 7 ft visibility. Maximum depth: 52 ft. Surface area: 37.16 acres.
- Clarity
- 7 ft
- Max depth
- 52 ft
- Area
- 37 acres
- Public access
- No
Next lake in Cook County
Why Copper Lake has no grade
We grade a lake only when its monitoring record clears the evidence bar: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Copper Lake, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years). Sampling here has recorded water clarity, but not phosphorus and algae (chlorophyll-a).
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by MPCA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Copper Lake is a 37-acre lake in Cook County, Minnesota with a maximum depth of 52 feet. Limited fish-species data available. No public access — the lake is private or restricted.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2020-08-03. Grade methodology: LakeGrade methodology.
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Copper Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Moderate clarity, visible to about 7 ft. Trophic State Index: 49.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 7 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 49 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Copper Lake
Compare lakeside cabins, hotels, and vacation rentals near Copper Lake in Cook County, Minnesota — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Copper Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 52 ft |
| Surface Area | 37 acres |
| Shoreline Length | 2.5 mi |
| Littoral Zone | 65% |
| Public Access | No |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Fishing Copper Lake
DNR Fisheries Survey Summary
1 survey on file from MN DNR Fisheries. Most recent: 1989-07-17 (Standard Survey).
Top Species by Catch Rate
| Species | Avg CPUE | Avg Weight |
|---|---|---|
| Northern Pike | 1.75 | 1.71 lb |
| White Sucker | 0.75 | 0.17 lb |
| BUB | 0.50 | 0.25 lb |
CPUE = catch per unit effort, averaged across surveys (excludes juvenile shoreline seining). Higher CPUE = more abundant in standardized sampling.
From the 1989-07-17 survey
A FEW NORTHERN PIKE ARE PRESENT, BUT NO LARGE FISH WERE SAMPLED. THERE APPEARS TO BE A RELA- TIVELY STRONG 1986 YEAR CLASS, BUT SEVERAL OTHERS ARE WEAK OR MISSING. GROWTH IS FAST BY COOK COUNTY STANDARDS.
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Copper Lake. 1 report on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — CopperFisheries Lake Survey · MN DNR LakeFinder
Graded lakes near Copper Lake
Copper Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Cook County
Frequently asked questions about Copper Lake
What is the water quality grade for Copper Lake?
- Copper Lake in Cook County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 7 ft visibility. Maximum depth: 52 ft. Surface area: 37.16 acres.
Is Copper Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Copper Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
How deep is Copper Lake?
- Copper Lake has a maximum depth of 52 feet. The lake covers 37.16 acres.
Explore Copper Lake across LakeGrade
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Where this data comes from
1 measurement from 1 monitoring station, 2020. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA1 sample · 2020
Analytical methods
- Field measurement/observation, generic method
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder